From: Jakub Jelinek <jakub@redhat.com>
To: Ulrich Drepper <drepper@redhat.com>
Cc: Glibc hackers <libc-hacker@sources.redhat.com>
Subject: [PATCH] fenv fixes for x86_64/i386/ia64
Date: Thu, 22 Mar 2007 14:49:00 -0000 [thread overview]
Message-ID: <20070322145345.GZ1826@sunsite.mff.cuni.cz> (raw)
Hi!
feholdexcept is supposed to clear the sticky exception bits:
"The feholdexcept function saves the current floating-point environment in the object
pointed to by envp, clears the floating-point status flags, and then installs a non-stop
(continue on floating-point exceptions) mode, if available, for all floating-point
exceptions."
and
"A floating-point status flag is a system variable whose value is set
(but never cleared) when a floating-point exception is raised, which occurs as a side effect
of exceptional floating-point arithmetic to provide auxiliary information."
Several feholdexcept implementations didn't handle this right.
Also, e.g. feupdateenv was a stub on x86_64 eventhough it is IMHO easily
implementable and other arches had bugs in it too (e.g. ia64 would rise
wrong exceptions and always return a failure).
I added a new testcase for feholdexcept/feupdateenv (hopefully I haven't
misinterpreted the standard) and I believe other arches (ppc*, s390*, ...)
will need some care too.
2007-03-22 Jakub Jelinek <jakub@redhat.com>
[BZ #3427]
* sysdeps/x86_64/fpu/feholdexcpt.c (feholdexcept): Clear all
exceptions both in SW and MXCSR.
* sysdeps/x86_64/fpu/feupdateenv.c: New file.
* sysdeps/x86_64/fpu/feenablxcpt.c (feenableexcept): Remove dead code.
* sysdeps/x86_64/fpu/fedisblxcpt.c (fedisableexcept): Likewise.
* sysdeps/i386/fpu/feholdexcpt.c (feholdexcept): Clear all exceptions
in MXCSR if SSE is available.
* sysdeps/i386/fpu/feupdateenv.c: Include unistd.h, dl-procinfo.h
and ldsodefs.h.
(__feupdateenv): Query exceptions also from MXCSR if SSE is available.
Fix comment typo.
* sysdeps/ia64/fpu/feholdexcpt.c (feholdexcept): Clear all exceptions.
Return 0 rather than 1.
* sysdeps/ia64/fpu/feupdateenv.c (feupdateenv): Fix comment typo.
Remove incorrect part of a comment. Fix argument to feraiseexcept.
* math/test-fenv.c (feholdexcept_tests): New function.
(main): Call it.
2007-01-05 Richard B. Kreckel <kreckel@ginac.de>
[BZ #3427]
* sysdeps/i386/fpu/feholdexcpt.c (feholdexcept): Clear all exceptions
in SW.
--- libc/math/test-fenv.c.jj 2003-05-22 04:08:50.000000000 +0200
+++ libc/math/test-fenv.c 2007-03-22 14:41:33.000000000 +0100
@@ -1,4 +1,5 @@
-/* Copyright (C) 1997, 1998, 2000, 2001, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 1997, 1998, 2000, 2001, 2003, 2007
+ Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Jaeger <aj@suse.de> and
Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -636,6 +637,102 @@ feenv_tests (void)
}
+static void
+feholdexcept_tests (void)
+{
+ fenv_t saved, saved2;
+ int res;
+
+ feclearexcept (FE_ALL_EXCEPT);
+ fedisableexcept (FE_ALL_EXCEPT);
+#ifdef FE_DIVBYZERO
+ feraiseexcept (FE_DIVBYZERO);
+#endif
+ test_exceptions ("feholdexcept_tests FE_DIVBYZERO test",
+ DIVBYZERO_EXC, 0);
+ res = feholdexcept (&saved);
+ if (res != 0)
+ {
+ printf ("feholdexcept failed: %d\n", res);
+ ++count_errors;
+ }
+#if defined FE_TONEAREST && defined FE_TOWARDZERO
+ res = fesetround (FE_TOWARDZERO);
+ if (res != 0)
+ {
+ printf ("fesetround failed: %d\n", res);
+ ++count_errors;
+ }
+#endif
+ test_exceptions ("feholdexcept_tests 0 test", NO_EXC, 0);
+ feraiseexcept (FE_INVALID);
+ test_exceptions ("feholdexcept_tests FE_INVALID test",
+ INVALID_EXC, 0);
+ res = feupdateenv (&saved);
+ if (res != 0)
+ {
+ printf ("feupdateenv failed: %d\n", res);
+ ++count_errors;
+ }
+#if defined FE_TONEAREST && defined FE_TOWARDZERO
+ res = fegetround ();
+ if (res != FE_TONEAREST)
+ {
+ printf ("feupdateenv didn't restore rounding mode: %d\n", res);
+ ++count_errors;
+ }
+#endif
+ test_exceptions ("feholdexcept_tests FE_DIVBYZERO|FE_INVALID test",
+ DIVBYZERO_EXC | INVALID_EXC, 0);
+ feclearexcept (FE_ALL_EXCEPT);
+ feraiseexcept (FE_INVALID);
+#if defined FE_TONEAREST && defined FE_UPWARD
+ res = fesetround (FE_UPWARD);
+ if (res != 0)
+ {
+ printf ("fesetround failed: %d\n", res);
+ ++count_errors;
+ }
+#endif
+ res = feholdexcept (&saved2);
+ if (res != 0)
+ {
+ printf ("feholdexcept failed: %d\n", res);
+ ++count_errors;
+ }
+#if defined FE_TONEAREST && defined FE_UPWARD
+ res = fesetround (FE_TONEAREST);
+ if (res != 0)
+ {
+ printf ("fesetround failed: %d\n", res);
+ ++count_errors;
+ }
+#endif
+ test_exceptions ("feholdexcept_tests 0 2nd test", NO_EXC, 0);
+ feraiseexcept (FE_INEXACT);
+ test_exceptions ("feholdexcept_tests FE_INEXACT test",
+ INEXACT_EXC, 0);
+ res = feupdateenv (&saved2);
+ if (res != 0)
+ {
+ printf ("feupdateenv failed: %d\n", res);
+ ++count_errors;
+ }
+#if defined FE_TONEAREST && defined FE_UPWARD
+ res = fegetround ();
+ if (res != FE_UPWARD)
+ {
+ printf ("feupdateenv didn't restore rounding mode: %d\n", res);
+ ++count_errors;
+ }
+ fesetround (FE_TONEAREST);
+#endif
+ test_exceptions ("feholdexcept_tests FE_INEXACT|FE_INVALID test",
+ INVALID_EXC | INEXACT_EXC, 0);
+ feclearexcept (FE_ALL_EXCEPT);
+}
+
+
/* IEC 559 and ISO C99 define a default startup environment */
static void
initial_tests (void)
@@ -654,6 +751,7 @@ main (void)
initial_tests ();
fe_tests ();
feenv_tests ();
+ feholdexcept_tests ();
if (count_errors)
{
--- libc/sysdeps/ia64/fpu/feholdexcpt.c.jj 2005-07-08 20:52:46.000000000 +0200
+++ libc/sysdeps/ia64/fpu/feholdexcpt.c 2007-03-22 13:28:45.000000000 +0100
@@ -1,5 +1,5 @@
/* Store current floating-point environment and clear exceptions.
- Copyright (C) 1997, 1999, 2000, 2005 Free Software Foundation, Inc.
+ Copyright (C) 1997, 1999, 2000, 2005, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Christian Boissat <Christian.Boissat@cern.ch>, 1999
@@ -23,12 +23,20 @@
int
feholdexcept (fenv_t *envp)
{
+ fenv_t fpsr;
/* Save the current state. */
- fegetenv (envp);
+ __asm__ __volatile__ ("mov.m %0=ar.fpsr" : "=r" (fpsr));
+ *envp = fpsr;
- /* set the trap disable bit */
- __asm__ __volatile__ ("mov.m ar.fpsr=%0" :: "r" (*envp | FE_ALL_EXCEPT));
+ /* Set the trap disable bits. */
+ fpsr |= FE_ALL_EXCEPT;
- return 1;
+ /* And clear the exception bits. */
+ fpsr &= ~(fenv_t) (FE_ALL_EXCEPT << 13);
+
+ __asm__ __volatile__ ("mov.m ar.fpsr=%0" :: "r" (fpsr));
+
+ /* Success. */
+ return 0;
}
libm_hidden_def (feholdexcept)
--- libc/sysdeps/ia64/fpu/feupdateenv.c.jj 2001-07-06 06:55:54.000000000 +0200
+++ libc/sysdeps/ia64/fpu/feupdateenv.c 2007-03-22 13:27:28.000000000 +0100
@@ -1,5 +1,5 @@
/* Install given floating-point environment and raise exceptions.
- Copyright (C) 1997, 2000 Free Software Foundation, Inc.
+ Copyright (C) 1997, 2000, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Christian Boissat <Christian.Boissat@cern.ch>, 1999.
@@ -32,10 +32,8 @@ feupdateenv (const fenv_t *envp)
/* Install new environment. */
fesetenv (envp);
- /* Raise the safed exception. Incidently for us the implementation
- defined format of the values in objects of type fexcept_t is the
- same as the ones specified using the FE_* constants. */
- feraiseexcept ((int) fpsr & FE_ALL_EXCEPT);
+ /* Raise the saved exceptions. */
+ feraiseexcept ((int) (fpsr >> 13) & FE_ALL_EXCEPT);
/* Success. */
return 0;
--- libc/sysdeps/i386/fpu/feholdexcpt.c.jj 2005-07-08 20:52:47.000000000 +0200
+++ libc/sysdeps/i386/fpu/feholdexcpt.c 2007-03-22 14:56:35.000000000 +0100
@@ -1,5 +1,6 @@
/* Store current floating-point environment and clear exceptions.
- Copyright (C) 1997, 1999, 2003, 2004, 2005 Free Software Foundation, Inc.
+ Copyright (C) 1997, 1999, 2003, 2004, 2005, 2007
+ Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -26,14 +27,19 @@
int
feholdexcept (fenv_t *envp)
{
- unsigned short int work;
+ fenv_t temp;
/* Store the environment. */
- __asm__ ("fnstenv %0" : "=m" (*envp));
+ __asm__ ("fnstenv %0" : "=m" (temp));
+ *envp = temp;
/* Now set all exceptions to non-stop. */
- work = envp->__control_word | 0x3f;
- __asm__ ("fldcw %0" : : "m" (*&work));
+ temp.__control_word |= 0x3f;
+
+ /* And clear all exceptions. */
+ temp.__status_word &= ~0x3f;
+
+ __asm__ ("fldenv %0" : : "m" (temp));
/* If the CPU supports SSE we set the MXCSR as well. */
if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
@@ -43,8 +49,8 @@ feholdexcept (fenv_t *envp)
/* Get the current control word. */
__asm__ ("stmxcsr %0" : "=m" (*&xwork));
- /* Set all exceptions to non-stop. */
- xwork |= 0x1f80;
+ /* Set all exceptions to non-stop and clear them. */
+ xwork = (xwork | 0x1f80) & ~0x3f;
__asm__ ("ldmxcsr %0" : : "m" (*&xwork));
}
--- libc/sysdeps/i386/fpu/feupdateenv.c.jj 2001-07-06 06:55:53.000000000 +0200
+++ libc/sysdeps/i386/fpu/feupdateenv.c 2007-03-22 14:47:22.000000000 +0100
@@ -1,5 +1,5 @@
/* Install given floating-point environment and raise exceptions.
- Copyright (C) 1997,99,2000,01 Free Software Foundation, Inc.
+ Copyright (C) 1997,99,2000,01,07 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -20,20 +20,29 @@
#include <fenv.h>
#include <bp-sym.h>
+#include <unistd.h>
+#include <dl-procinfo.h>
+#include <ldsodefs.h>
int
__feupdateenv (const fenv_t *envp)
{
fexcept_t temp;
+ unsigned int xtemp = 0;
/* Save current exceptions. */
__asm__ ("fnstsw %0" : "=m" (*&temp));
- temp &= FE_ALL_EXCEPT;
+
+ /* If the CPU supports SSE we test the MXCSR as well. */
+ if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+ __asm__ ("stmxcsr %0" : "=m" (*&xtemp));
+
+ temp = (temp | xtemp) & FE_ALL_EXCEPT;
/* Install new environment. */
fesetenv (envp);
- /* Raise the safed exception. Incidently for us the implementation
+ /* Raise the saved exception. Incidently for us the implementation
defined format of the values in objects of type fexcept_t is the
same as the ones specified using the FE_* constants. */
feraiseexcept ((int) temp);
--- libc/sysdeps/x86_64/fpu/feholdexcpt.c.jj 2005-07-08 20:52:45.000000000 +0200
+++ libc/sysdeps/x86_64/fpu/feholdexcpt.c 2007-03-22 11:46:47.000000000 +0100
@@ -1,5 +1,5 @@
/* Store current floating-point environment and clear exceptions.
- Copyright (C) 2001, 2005 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2005, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -22,19 +22,24 @@
int
feholdexcept (fenv_t *envp)
{
- unsigned short int work;
unsigned int mxcsr;
+ fenv_t temp;
/* Store the environment. */
__asm__ ("fnstenv %0\n"
- "stmxcsr %1" : "=m" (*envp), "=m" (envp->__mxcsr));
+ "stmxcsr %1" : "=m" (temp), "=m" (temp.__mxcsr));
+ *envp = temp;
/* Now set all exceptions to non-stop, first the x87 FPU. */
- work = envp->__control_word | 0x3f;
- __asm__ ("fldcw %0" : : "m" (*&work));
+ temp.__control_word |= 0x3f;
+
+ /* And clear all exceptions. */
+ temp.__status_word &= ~0x3f;
+
+ __asm__ ("fldenv %0" : : "m" (temp));
/* Set the SSE MXCSR register. */
- mxcsr = envp->__mxcsr | 0x1f80;
+ mxcsr = (envp->__mxcsr | 0x1f80) & ~0x3f;
__asm__ ("ldmxcsr %0" : : "m" (*&mxcsr));
return 0;
--- libc/sysdeps/x86_64/fpu/feupdateenv.c.jj 2007-03-22 12:11:41.000000000 +0100
+++ libc/sysdeps/x86_64/fpu/feupdateenv.c 2007-03-22 12:19:23.000000000 +0100
@@ -0,0 +1,51 @@
+/* Install given floating-point environment and raise exceptions.
+ Copyright (C) 1997,99,2000,01,07 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <fenv.h>
+
+int
+__feupdateenv (const fenv_t *envp)
+{
+ fexcept_t temp;
+ unsigned int xtemp;
+
+ /* Save current exceptions. */
+ __asm__ ("fnstsw %0\n\tstmxcsr %1" : "=m" (*&temp), "=m" (xtemp));
+ temp = (temp | xtemp) & FE_ALL_EXCEPT;
+
+ /* Install new environment. */
+ fesetenv (envp);
+
+ /* Raise the saved exception. Incidently for us the implementation
+ defined format of the values in objects of type fexcept_t is the
+ same as the ones specified using the FE_* constants. */
+ feraiseexcept ((int) temp);
+
+ /* Success. */
+ return 0;
+}
+
+#include <shlib-compat.h>
+#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2)
+strong_alias (__feupdateenv, __old_feupdateenv)
+compat_symbol (libm, __old_feupdateenv, feupdateenv, GLIBC_2_1);
+#endif
+
+versioned_symbol (libm, __feupdateenv, feupdateenv, GLIBC_2_2);
--- libc/sysdeps/x86_64/fpu/feenablxcpt.c.jj 2001-09-19 12:23:17.000000000 +0200
+++ libc/sysdeps/x86_64/fpu/feenablxcpt.c 2007-03-22 11:24:28.000000000 +0100
@@ -1,5 +1,5 @@
/* Enable floating-point exceptions.
- Copyright (C) 2001 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Jaeger <aj@suse.de>, 2001.
@@ -24,7 +24,7 @@ int
feenableexcept (int excepts)
{
unsigned short int new_exc, old_exc;
- unsigned int new, old;
+ unsigned int new;
excepts &= FE_ALL_EXCEPT;
@@ -40,8 +40,6 @@ feenableexcept (int excepts)
__asm__ ("stmxcsr %0" : "=m" (*&new));
/* The SSE exception masks are shifted by 7 bits. */
- old = (~new) & (FE_ALL_EXCEPT << 7);
-
new &= ~(excepts << 7);
__asm__ ("ldmxcsr %0" : : "m" (*&new));
--- libc/sysdeps/x86_64/fpu/fedisblxcpt.c.jj 2001-09-19 12:23:17.000000000 +0200
+++ libc/sysdeps/x86_64/fpu/fedisblxcpt.c 2007-03-22 11:26:35.000000000 +0100
@@ -1,5 +1,5 @@
/* Disable floating-point exceptions.
- Copyright (C) 2001 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Jaeger <aj@suse.de>, 2001.
@@ -24,7 +24,7 @@ int
fedisableexcept (int excepts)
{
unsigned short int new_exc, old_exc;
- unsigned int new, old;
+ unsigned int new;
excepts &= FE_ALL_EXCEPT;
@@ -40,8 +40,6 @@ fedisableexcept (int excepts)
__asm__ ("stmxcsr %0" : "=m" (*&new));
/* The SSE exception masks are shifted by 7 bits. */
- old = (~new) & (FE_ALL_EXCEPT << 7);
-
new |= excepts << 7;
__asm__ ("ldmxcsr %0" : : "m" (*&new));
Jakub
next reply other threads:[~2007-03-22 14:49 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-03-22 14:49 Jakub Jelinek [this message]
2007-03-22 21:46 ` Steven Munroe
2007-03-27 15:53 ` [PATCH] PPC fenv fixes Steven Munroe
[not found] ` <20070327160708.GA355@devserv.devel.redhat.com>
2007-03-27 18:07 ` Steven Munroe
2007-03-28 15:29 ` Steven Munroe
2007-04-05 2:27 ` Richard Henderson
2007-04-05 22:00 ` [PATCH] PPC fenv fixes. 3rd update Steven Munroe
2007-04-14 17:32 ` Jakub Jelinek
2007-04-17 0:09 ` Richard Henderson
[not found] ` <20070417002157.GI355@devserv.devel.redhat.com>
2007-04-30 21:45 ` Steven Munroe
2007-04-02 16:43 ` [PATCH] [PORTS] PPC fenv fixes for soft-fp Steven Munroe
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